Module 7.) Data Analysis and Risk Categorization Flashcards
The degree or amount of risk that the owner, manager, or controlling authority is willing to accept.
Acceptable Risk
A tool for categorizing the combined likelihood of a failure impacting a target.
Likelihood Matrix
A rectangular array of rows and columns used to facilitate problem solving or decision making.
Matrix
The concept that any tree, part, or failure mode could represent more than one type of risk.
Multiple Risks
The process of assigning risk and risk factors to categories based on the severity or hierarchy.
Risk Categorization
The process of comparing the assessed risk against given risk criteria to determine the significance of the risk
Risk Evaluation
A tool for ranking and displaying risks by assigning ratings for consequences and likelihood.
Risk rating matrix
The subjective perceived level of risk from a situation or object, often differing from the actual level of risk.
Risk Perception
Degree of risk that is acceptable to the owner, manager, or controlling authority.
Risk Tolerance
Time period for which an assessment is defined
Time Frame.
T - F When more than one defect or condition is present in a tree, the defects should be considered alone and in combination with other conditions
True
T-F When there are multiple levels of risk within a tree, identify the failure mode having the greatest risk and report that as the overall risk rating.
true
T-F How people perceive risk and their need for personal safety is inherently subjective; therefore, risk tolerance and acceptable risk thresholds vary among tree owners/ managers.
True
Combine the likelihood of failure and impact with the expected consequences of failure to determine a risk rating using the ____ _____ ___ ______
Risk rating matrix
Likelihood of failure
Imminent,
Probable,
Possible,
Improbable,
Likelihood of Impact
High,
Medium,
Low,
Very low.
Likelihood of failure and impact
Very likely,
Likely,
Somewhat likely,
unlikely.
Consequences of failure
Severe,
Significant,
Minor,
Negligible.
Risk Rating
Extreme,
High,
Moderate,
Low
T-F When more than one defect or condition is present in a tree, the defects should be considered alone and in combination with other conditions.
True
T - F When there are multiple levels of risk within a tree, identify the failure mode having the greatest risk and report that as the overall risk rating.
True
T - F How people perceive risk and their need for personal safety is inherently subjective; therefore, risk tolerance and acceptable risk thresholds vary among tree owners/managers.
True
If the risk rating of a whole-tree failure is rated as low, and the risk rating of a branch failure is rated as high, what is the tree's overall risk rating? A.) Low, B.) Moderate, C.) High, D.) Extreme
C.
Various risk posed by a tree cannot be added using matrix methodology, instead, the tree assessors should identify-among all the failure modes and consequences assessed-the greatest risk and report that as the tree risk rating. in this example, the greatest risk is the branch failure that is rated as high, so the overall risk rating would be high
A tree in which a failure has started or is most likely to occur in the near future, even if there is no significant wind or increased load, would be categorized with a likelihood of failure of A,) Imminent, B.) Probable, C.) Possible, D.) Improbable.
A.)
A tree with a failure that has already started has an Imminent likelihood of failure. Trees categorized with an imminent likelihood of failure may be infrequent, but require immediate action to protect people from harm.
To estimate likelihood of impact, the arborist should attempt to determine.
A.) The occupancy rate of targets within the target zone
B.) factors that could affect the direction of the tree’s fall,
C.) Factors that could protect the target.
D.) All of the above.
D.)
Factors that affect the likelihood of impact include occupancy rate, direction of fall, protection factors, and location with the target zone.
All of the following are the tree risk assessor’s responsibility in the risk evaluation process EXCEPT.
A.) Presenting the level of risk determined
B.) providing the mitigation options
C.) Describing the residual risk after mitigation.
D.Deciding which mitigation actions to take, If any
D.
Risk evaluation is the process of comparing the assessed risk against given risk criteria to determine the significance of the risk. The risk assessor presents the level of the risk that was determined, the recommend mitigation actions or options, and their associated residual risks, the tree owner or risk manager must then decide on what actions, if any, to take.